| 摘要 |
<p>PURPOSE:To decrease the side lobes occurring in Fresnel ripples by constituting a signal generating part of a means for storing the chirp signal subjected to a frequency predistortion and a control circuit for controlling the reading out of this memory means. CONSTITUTION:The chirp signal waveform subjected to the frequency predistortion is previously set in a memory circuit 12 and the memory content of the circuit 12 is read out by the reading out control circuit 11, by which the prescribed chirp signal is applied to a signal transmission part 13. This chirp signal is amplified in the transmission part 13 and is radiated to the space via a signal transmitting/receiving and demultiplexing part 14. After the chirp signal is reflected by a target, the signal is amplified in a signal receiving part 16 via the antenna 15 and the demultiplexing part 14. The amplified chirp signal is subjected to time compression in a pulse compression part 17 consisting of a chirp filter 18 for pulse compression and is converted to an impulse signal; following which said signal is detected 19. Since the transmitted output waveform is subjected to the frequency predistortion, the Fresnel ripples generated in the spectra are improved. The side lobes in the output waveform of the filter 18 are, therefore, decreased.</p> |
